Soil Compacting Device with Compensating Coupling

ABSTRACT

A soil compacting device has an upper mass having a drive and a lower mass having an imbalance exciter. On the lower mass, there is provided a bearer device connected fixedly thereto, which bearer device bears a transmission device having an input shaft and an output shaft. The drive has a drive shaft that is coupled to the input shaft. The imbalance exciter has an exciter shaft that is coupled to the output shaft. A compensating coupling is provided between the drive shaft of the drive and the input shaft of the transmission device. The compensating coupling is designed to compensate for an axial offset, a radial offset, and an angular offset between the drive shaft and the input shaft.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a soil compacting device, such as a vibrating plate or vibratory plate compactor.

2. Description of the Related Art

Vibrating plates for soil compaction are known. They are standardly designed such that they have an upper mass, which bears a drive motor, and a lower mass, coupled to the upper mass so as to be movable relative thereto. On the lower mass, there is provided an imbalance exciter that is attached to a soil contact plate and that, during operation, introduces vibrations into this plate. The vibrations are transferred into the soil to be compacted via the soil contact plate.

The imbalance exciter can standardly have one, two, or three imbalance shafts that are rotationally driven. When there is rotation of the imbalance shaft or shafts, due to the imbalance mass attached to the respective imbalance shaft (a plurality of imbalance masses may also be attached) the desired imbalance forces arise, which cause the vibrations.

For the drive of the imbalance exciter, two systems have primarily proven successful, namely a hydrostatic drive and a V-belt drive.

In the hydrostatic drive, hydraulic oil is pressurized via a gear pump seated on an internal combustion engine on the upper mass, which oil drives a gear motor seated on the lower mass and fastened to the imbalance exciter. The two gear units are connected to one another via hydraulic hoses. The compensation of the relative movements between the upper mass and the lower manse is enabled by the flexibility of the hydraulic hoses.

An example of a vibrating plate generally known from the prior art having a V-belt drive is shown in FIGS. 5A and 5B; here FIG. 5A shows a highly schematized side view and FIG. 5B shows a view from the rear.

In a V-belt drive, a first V-belt pulley 51 is provided on an internal combustion engine 52, which is always installed transversely, on an upper mass 53. A second V-belt pulley 54 is fastened on an exciter shaft 55, which is always installed transversely, on an imbalance exciter 56 of a lower mass 57. A V-belt 58 that runs over both pulleys 51, 54 transmits power and compensates the relative movements that occur during operation between upper mass 53 and lower mass 57.

The required V-belt tension in V-belt drives is frequently achieved through self-tensioning pulleys. Alternatively, a tension roller can also be provided that tensions the belt and is adjusted manually using a tool. In these tensioning systems, only the average required belt tension is applied. These systems are relatively sluggish and are capable only to a certain extent of compensating the rapid relative movements that occur during vibration operation between the upper mass and the lower mass, and the associated changes in axial spacing between the two shafts.

Due to the permanent relative movement between the upper mass and the lower mass, the V-belt circulating between the two pulleys is exposed to significant load, for which it is usually not designed. The lifespans indicated by the manufacturers of commercially available V-belts can be achieved only if the pulleys have a defined, constant axial spacing and a high degree of parallel alignment to each other. In addition, a dust-free environment is presupposed, in particular one that is free of abrasive media.

Because these requirements cannot be met during operation of a belt-driven vibrating plate, the service life of the V-belt is greatly limited. Failure of the belt results in a longer period of machine downtime, due to the work necessary to exchange the belt. In addition, the constantly changing axial distance enables an increased degree of slippage in the belt drive, which has a negative influence on the overall efficiency of the drive system.

In comparison, the hydrostatic drive of the imbalance exciter has proven very successful in practice. However, it requires a significant additional constructive outlay, resulting in significantly greater weight and higher costs. For these reasons, the hydrostatic drive is mostly installed only in high-power vibrating plates. In smaller vibrating plates, in contrast, the inexpensive and economical V-belt drive is used.

SUMMARY OF THE INVENTION

The object of the present invention is to indicate a soil compacting device in which the drive power can be transmitted from the drive present on the upper mass to the imbalance exciter on the lower mass in a constructively simple and thus low-cost manner.

This object is achieved by providing a soil compacting device that has an upper mass that has a drive, a lower mass that is connected to the upper mass so as to be movable relative thereto, and a soil contact plate for soil compaction, an imbalance exciter provided on the lower mass and capable of being driven by the drive, and having a bearer device situated on the upper mass or on the lower mass and connected fixedly thereto. The bearer device has a transmission or gearbox device having an input shaft and an output shaft that are coupled by a torque-transmitting device for the transmission of a torque from the input shaft to the output shaft. The bearer device bears the input shaft and the output shaft so as to be capable of rotation. The drive has a drive shaft that is coupled to the input shaft. The imbalance exciter has an exciter shaft that is coupled to the output shaft. Between the drive shaft of the drive and the input shaft of the transmission device or, in an alternative specific embodiment, between the output shaft of the transmission device and the exciter shaft of the imbalance exciter, a compensating coupling is provided. The compensating coupling is designed to compensate an axial offset, a radial offset, and an angular offset between the drive shaft and the input shaft, or, in the alternative specific embodiment, between the output shaft and the exciter shaft.

The soil compacting device can for example be a vibrating plate or a vibratory soil compactor. Here, the upper mass is essentially made up of the drive, for example an internal combustion engine or an electric motor. In addition, the upper mass can have further components, such as a fuel tank, a battery, control elements, covers, and a steering bar for steering the soil compacting device.

The lower mass includes in particular the soil contact plate for compacting the soil and the imbalance exciter, which introduces the desired vibrations into the soil contact plate.

The upper mass and the lower mass are movable relative to each other, so that under the influence of the vibrations the lower mass can move as freely as possible, while the upper mass should be decoupled as well as possible from the vibrations, and thus at rest. For this purpose, a vibration decoupling device is provided between the upper mass and the lower mass, for example a spring device or a spring-damper device. In practice, in particular rubber buffers have proven successful for the connection between the upper mass and the lower mass.

The compensating coupling is provided at the system boundary between the lower mass and the upper mass, in particular at the location where the relative movement takes place between a shaft component mounted on the lower mass and a shaft component mounted on the upper mass. Because the compensating coupling is capable of compensating an axial offset, a radial offset, and an angular offset, it can compensate all the relative movements between the upper mass and lower mass.

The drive shaft of the drive is to be understood broadly. The drive shaft is intended to be the output of the drive and can for example be connected downstream from a transmission appertaining to the drive, or from a centrifugal clutch also appertaining to the drive. In this way, the drive shaft can be realized as a solid shaft, but also as a hollow shaft or bell (e.g. in a centrifugal clutch).

The various shafts indicated above, namely the drive shaft and the input shaft on the one hand and the output shaft and the exciter shaft on the other hand, can, if the compensating coupling is not to be connected between them, also be realized identical to one another, i.e. in particular can be made in one piece. Thus, it is not absolutely necessary for the two shaft elements situated opposite one another to be separate components. Rather, for example in a simpler design, the exciter shaft and the output shaft may be fashioned as a one-piece shaft.

The bearer device performs a central function. Depending on the specific embodiment, it can be rigidly connected to the upper mass or to the lower mass, to one of the components provided there. For example, the bearer device on the lower mass can be fixedly or rigidly connected to the imbalance exciter and/or to the soil contact plate, thus forming a unit.

The bearer device bears the input shaft and the output shaft and holds the two in a constant position relative to each other. In particular, the bearer device ensures that the input shaft and the output shaft have a constant shaft spacing, even during vibration operation, and run in the specified angular position, i.e. for example parallel to one another, or also at a right angle to one another. In this way, the problem that arises in vibratory soil compactors known from the prior art, of an axial spacing that constantly changes during vibrating operation, can be avoided. In this way, it is in particular ensured, as explained below, that for example two pulleys attached to the input shaft and the output shaft, and between which there runs a V-belt, always have the same axial spacing, with a high degree of parallel alignment. In this way, a long lifespan of the V-belt can be achieved.

Due to its stiff, rigid design, the bearer device makes it possible for the transmission device that it bears to perform its intended function over the long term.

The transmission device, and the torque-transmitting device provided in this connection, can be a belt drive or chain drive. It is also possible for the transmission device to be realized as a gear transmission or spur gear system.

In a specific embodiment, the bearer device is fixedly connected to the upper mass. The compensating coupling is then provided between the output shaft of the transmission device and the exciter shaft of the imbalance exciter, the compensating coupling being designed to compensate an axial offset, a radial offset, and an angular offset between the output shaft and the exciter shaft.

In this case, the bearer device is connected to the upper mass rigidly, or with a high degree of stiffness. The bearer device ensures the constant axial spacing between the input shaft and the output shaft coupled to the drive. The relative movement that then prevails during operation between the output shaft and the exciter shaft is compensated by the compensating coupling, so that the drive power can be transmitted from the output shaft to the exciter shaft.

In another specific embodiment, the bearer device is connected to the lower mass fixedly or rigidly, i.e. with a high degree of stiffness. In this case, the compensating coupling is provided between the drive shaft of the drive and the input shaft of the transmission device, the compensating coupling then being designed to compensate an axial offset, a radial offset, and an angular offset between the drive shaft and the input shaft.

In this alternative specific embodiment, the bearer device is thus attached to the lower mass, for example to the imbalance exciter, with a high degree of rigidity. Here as well, the bearer device is able to hold constant the axial spacing between the input shaft and the output shaft of the transmission device. In this way, the relative movement takes place between the drive shaft coming from the drive and the input shaft of the transmission device. The compensating coupling is situated there in order to compensate this relative movement.

The bearer device and the transmission device can be at least partly enclosed by a transmission housing. In particular, it is advantageous if the components of the transmission device, in particular the torque-transmitting device, are enclosed largely completely by the transmission housing, and are thus encapsulated relative to the surrounding environment. For example, the transmission housing can be realized as a belt drive housing and can encapsulate the belt that transmits the torque from the surrounding environment.

The transmission housing can have sheet elements that are fastened to the bearer device in order to form the housing. The bearer device can for example be fashioned as a cast part or welded part.

The bearer device can be connected rigidly to the soil contact plate and/or to an exciter housing appertaining to the imbalance exciter.

In this specific embodiment, it is advantageous if the input shaft is aligned with the drive shaft of the drive in an idle state of the soil compacting device. This means that the axes of rotation of the input shaft and the output shaft are aligned. In contrast, during vibration operation the rotational axes can assume a multiple offset (axial, radial, and angular), which is then compensated by the compensating coupling.

The transmission device can be a belt drive having a first pulley and having a second pulley capable of being driven by the first pulley via a belt, for example a V-belt. The first pulley can be borne by the input shaft, while the second pulley can be borne by the output shaft. The exciter shaft of the imbalance exciter can be coupled to the output shaft, and thus to the second pulley, in such a way that it can be rotationally driven via the second pulley.

If the transmission device is thus realized as a belt drive, the belt can be selected from the group: V-belt, toothed belt, V-ribbed belt. Alternatively, the transmission device can be realized as a chain drive or gear drive.

The compensating coupling can be fashioned as a link coupling. Depending on the location at which the compensating coupling, or link coupling, is situated, the link coupling can have—if the compensating coupling, or link coupling, is situated between the drive shaft and the input shaft—a first crank that is coupled to the drive shaft, a second crank coupled to the input shaft, and a connecting rod that couples the first crank and the second crank, or—if the compensating coupling is situated between the output shaft and the exciter—the link coupling can have a first crank coupled to the output shaft, a second crank coupled to the exciter shaft, and a connecting rod coupling the first crank and the second crank.

The first crank and the second crank can be rotated by an angle relative to one another that is bridged by the connecting rod. The respective coupling point at which the connecting rod is coupled to the respective shaft is then for example situated respectively at one end of a boom of the crank.

The connecting rod can be pivotable by at least a small angle relative to the first crank and/or to the second crank. In particular, the connecting rod can be pivotable relative to the respective plane in which the respective crank is situated and rotates during operation. The connecting rod can be coupled to the first crank and/or to the second crank via an elastic bearing. With the aid of the elastic bearing, it is possible for the connecting rod to have the required ability to move relative to the first crank and to the second crank.

The elastic bearing can be an elastomer spherical bearing. The spherical bearing can be made up of an inner metal sleeve that has a spherical surface and an outer metal sleeve that has a spherical bore. The two metal sleeves are fastened to the crank, or to the connecting rod, in such a way that no relative movement occurs between them, i.e. in the respective seat. Between the two metal sleeves there is in turn situated an elastomer, such as rubber, having the required elasticity. The elastomer spherical bearing can thus both twist and also deflect cardanically.

The first crank and/or the second crank have a compensating mass situated, relative to their axis of rotation, opposite a coupling point to which the connecting arm is coupled. The compensating mass is used to compensate an imbalance that arises due to the coupling of the connecting rod to the boom of the respective crank. In this way, each crank can easily be balanced in itself together with the connecting rod coupled thereto.

In a specific embodiment, a centrifugal clutch is provided as part of the drive, and the drive shaft is then part of the centrifugal clutch. The drive shaft can here for example be fashioned as a bell, or part of the bell of the centrifugal clutch. In this way, it is possible for the first crank to be connected directly to the drive shaft of the centrifugal clutch.

According to the present invention, a bearer device is indicated that may be capable of being encapsulated by a housing, the device ensuring a defined axial distance between the input shaft and the output shaft, the two axes being capable of being held with a high degree of parallel alignment to one another. With the aid of the bearer or transmission housing, a clean environment, free of dust and foreign bodies, is ensured. Thus, in particular when the transmission device is realized as a belt drive, it is then possible for the life of the belt that is then used to exceed the assumed lifespan of the machine, and in this way long-term durability can be achieved.

The relative movements that occur during operation between the upper mass and lower mass are expressed in that at the free end of the bearer device, or of the rigid transmission housing, or belt drive housing, achieved by the bearer device, relative movements occur that are compensated by the compensating coupling. If the compensating coupling is fashioned in the form of the link coupling, this coupling can compensate the offsets and transmit the power.

These and further advantages and features of the present invention are explained in more detail below on the basis of examples, with the aid of the accompanying Figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a highly schematized side view of a soil compacting device according to the present invention;

FIG. 1B shows a rear view of the soil compacting device of FIG. 1A;

FIG. 1C shows an enlarged detail of FIG. 1B;

FIG. 2A shows a schematic side view of another specific embodiment of the soil compacting device;

FIG. 2B shows a rear view of the soil compacting device of FIG. 2A;

FIGS. 3A-3D show various views of a compensating coupling according to the present invention, as a link coupling;

FIG. 4A shows a side view of an elastomer spherical bearing;

FIG. 4B shows a sectional view of the elastomer spherical bearing;

FIG. 5A shows a schematic side view of a soil compacting device according to the prior art; and

FIG. 5B shows a rear view of the soil compacting device of FIG. 5A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1A (side view) and FIG. 1B (rear view) show a soil compacting device according to the present invention having an upper mass 1 that bears a drive 2, for example an internal combustion engine or an electric motor. Below upper mass 1, a lower mass 3 is provided that is coupled to upper mass 1 via a vibration decoupling device (not shown) and is movable relative to this upper mass. Lower mass 3 has a soil contact plate 4 and an imbalance exciter 5 that during operation imparts a vibration to soil contact plate 4.

Imbalance exciter 5 can be constructed in a known manner. In particular, imbalance exciter 5 can have for example one or two imbalance shafts, not shown in the Figures, that can be set into rotational movement by the drive in order to bring about the desired vibrations for the soil compaction.

A guide handle 6 having a control lever 7 is situated on upper mass 1.

Such a design of a vibrating plate is known from the prior art.

For the transmission of the drive power from drive 2 to imbalance exciter 5, a belt drive 8, acting as a transmission device, is provided. Belt drive 8 has various known components that are shown in the enlarged representation of FIG. 1C. These are, in particular, a first pulley 9, situated in the upper region, a second pulley 10, mounted in the lower region, and a V-belt 11 that circulates between first pulley 9 and second pulley 10.

Belt drive 8 is held by a bearer device 12 that is fastened rigidly to imbalance exciter 5, or to an exciter housing of imbalance exciter 5. Alternatively, bearer device 12 can also be attached directly on soil contact plate 4.

Bearer device 12 is in particular a construction that is realized to be as stiff or rigid as possible, e.g. as a cast or welded part, in order to enable the bearing functions required by bearer device 12.

At the output of drive 2 there is provided a drive shaft 13 that is aligned with an input shaft 14 of belt drive 8. First pulley 9 of belt drive 8 is mounted on input shaft 14. In the lower region, imbalance exciter 5 has an exciter shaft 15 that is aligned with an output shaft 16 of belt drive 8 and is coupled thereto. Exciter shaft 15 and output shaft 16 can also be realized in one piece as a shaft.

Second pulley 10 of belt drive 8 is mounted on output shaft 16.

Because both input shaft 14 and output shaft 16 are mounted in bearer device 12 together with first pulley 9 and second pulley 10, their axial spacing is held constant by bearer device 12. In addition, the parallel alignment of input shaft 14 and output shaft 16 is also maintained, including during operation.

Belt drive 8 can form, together with bearer device 12, a belt drive housing, and can thus seal the belt drive running in the interior from the external environment. In this case, only two bores are then to be provided through which on the one hand input shaft 14 and on the other hand output shaft 16 can extend. Because in this way a complete sealing of the belt drive housing in bearer device 12 can be achieved, no dust can penetrate. A penetration of dust can also be reduced through a corresponding fastening of bearer device 12 to the exciter housing of imbalance exciter 5.

Between drive shaft 13 and input shaft 14 there is provided a compensating coupling 17 that is used to compensate an axial offset, a radial offset, and an angular offset between drive shaft 13 and input shaft 14, and which is further explained below.

For the sealing of the housing of belt drive 8, a lateral cover 18 can be fastened on bearer device 12. Cover 18 can be mounted with a seal.

The relative movements that occur during operation of upper mass 1 and lower mass 3 are expressed in that the upper end of bearer device 12, with the housing of belt drive 8, and thus input shaft 14, comes closer to or moves away from the motor crankshaft or drive shaft 13 (axial offset), is displaced radially in all directions (radial offset), and that angular offsets occur between the two shafts (angular offset). Compensating coupling 17 compensates these offsets and transmits the drive power.

FIGS. 2A and 2B show another specific embodiment of the vibrating plate. The essential design of upper mass 1 and lower mass 3 is here identical to the specific embodiment of FIGS. 1A-1C.

However, differing from the variant of FIGS. 1A-1C, in the specific embodiment of FIGS. 2A and 2B, bearer device 12 is fastened fixedly or rigidly to upper mass 1. For example, bearer device 12 can be attached to the motor housing of drive 2. It is also possible to attach bearer device 12 to a bearing structure that is present on upper mass 1 but is not shown in FIGS. 2A and 2B. In any case, in this way bearer device 12 moves together with upper mass 1, so that the corresponding relative movement between upper mass 1 and lower mass 3 is present at the lower end of bearer device 12 on output shaft 16. Correspondingly, compensating coupling 17 is situated between output shaft 16 and exciter shaft 15.

If needed, compensating coupling 17 can be protected against the penetration of rocks by a bellows.

In the variant of FIGS. 2A and 2B, fewer movable components are situated on lower mass 3, which is strongly loaded with vibration, and this can improve the lifespan of these components. In addition, lower mass 3 is lighter, which can promote compacting power and can be favorable for the steering dynamics.

The design of compensating coupling 17 can be seen in FIGS. 3A-3D, where FIG. 3A shows the compensating coupling in a perspective view. FIG. 3B illustrates radial offset R, FIG. 3C shows an axial offset A, and FIG. 3D illustrates an angular offset W.

Compensating coupling 17 has a first crank 31 and a second crank 32. First crank 31 is connected to second crank 32 via a connecting rod 33. Connecting rod 33 is pivotable relative to each of the two cranks 31, 32 about an axis parallel to the shaft axes (cf. in particular FIG. 3B. In addition, connecting rod 33 is also pivotable about an axis that stands at an angle, e.g. perpendicular, to the shaft axes, in order to be able to execute the desired compensating movements (cf. FIGS. 3C and 3D).

For this purpose, connecting rod 33 is attached to a respective boom of crank 31, 32 by a respective spherical bearing 34, in particular an elastomer spherical bearing.

Compensating coupling 17, fashioned as a link coupling, can operate both in pulling fashion and in pushing fashion. That is, first crank 31 can push connecting rod 33 in front of it in the direction of rotation, so that second crank 32 is pushed. Alternatively, first crank 31 can also rotate and draw connecting rod 33 in the direction of rotation, so that second crank 32 is drawn along by connecting rod 33 and follows the movement.

Spherical bearing 34, fashioned as an elastomer spherical bearing, is shown in detail in FIGS. 4A and 4B, where FIG. 4A shows a front view and FIG. 4B shows a vertical section.

Correspondingly, elastomer spherical bearing 34 is made up of an inner metal sleeve 35 and an outer metal sleeve 36. Inner metal sleeve 35 has a spherical surface 37, while outer metal sleeve 36 has a spherical bore 38. Between spherical surface 37 and spherical bore 38 there is situated an elastomer 39, for example rubber.

The two metal sleeves 35, 36 are fastened to the respective crank 31, 32 and to connecting rod 33 in such a way that no relative movement occurs between the crank, or connecting rod, on the one hand, and the associated metal sleeve 35, 36 (cf. for example FIG. 3C). In contrast, the relative movement takes place exclusively between the two metal sleeves 35, 36, and is absorbed by elastomer 39. Spherical bearing 34 can thus both twist (FIG. 4A) and also deflect cardanically (FIG. 4B).

So that the link coupling (compensating coupling 17) does not itself produce a strong imbalance, which in turn could have negative effects on the respectively affected roller bearings (not shown), on the respective cranks 31, 32 a compensating mass 40 is provided at the booms situated opposite the coupling points of connecting rod 33. Each of the compensating masses 40 extends into the coupling center, so that each coupling half, made up of one of the cranks 31, 32, spherical bearing 34, compensating mass 40, respective fastening elements, and half of connecting rod 33, is always in itself balanced both statically and dynamically as long as the link coupling is not deflected. When there is a deflection of the link coupling, as a function of the deflection path there result smaller, subjectively imperceptible imbalance forces and corresponding resetting forces.

In the example shown in FIGS. 1A-1C, first crank 31 is fastened on drive shaft 13, or coupled thereto. Because it is entirely standard for a centrifugal clutch to be provided downstream from drive 2, so that during idling of drive 2 no torque is transmitted to imbalance exciter 5, and the centrifugal clutch closes, and the transmission of torque takes place, only when a particular rotational speed (switching rotational speed) is exceeded, drive shaft 13 can also be formed by a bell of the centrifugal clutch. In this case, first crank 31 can be attached directly on the bell (not shown in the Figures) of the centrifugal clutch (also not shown).

Second crank 32 is coupled to input shaft 14 or is attached thereon.

When first crank 31 is set into rotational movement by drive 2, this rotational movement is transmitted to second crank 32 via connecting rod 33.

When, due to the vibrating operation, the desired relative movement occurs between upper mass 1 and lower mass 3, this movement can be compensated in compensating coupling 17. If, for example, the two shafts, namely drive shaft 13 and input shaft 14, have an offset, then the two axes of cranks 31, 32 also have an offset. If for example the axes of cranks 31, 32 have a radial offset, spherical bearing 34 is alternately twisted in a respective direction within a rotation. When there is an axial offset of the two cranks 31, 32, spherical bearing 34 is deflected cardanically. When there is an angular offset, spherical bearing 34 is alternately cardanically deflected within a rotation.

The maximum movements that occur during operation between upper mass 1 and lower mass 3 are known to the manufacturer when designing a corresponding vibrating plate. From this, the maximum deflections of (elastomer) spherical bearing 34, and the frequency thereof, are ascertained, and in this way the spherical bearing can be designed so as to have long-term durability. In order to protect the spherical bearing against overloading in case of misuse, the offset between upper mass 1 and lower mass 3 can also be limited by stops.

In the specific embodiment of FIGS. 2A and 2B, compensating coupling 17 is situated in the lower region between output shaft 16 and exciter shaft 15. In this case, first crank 31 can be attached to output shaft 16 and second crank 32 can be attached to exciter shaft 15.

The link coupling is not sensitive to contamination, in particular to abrasive dust, because neither sliding or rolling friction between two bodies takes place. The friction takes place only internally, within elastomer 39. Only larger foreign bodies need be kept away from the link coupling, because at higher rotational speeds these are slung away and could thus present a danger.

In contrast to other known compensating couplings having a short constructive length, the link coupling offers a high transmissible torque in combination with comparatively high permissible offsets, in particular a high radial offset. All offsets can be increased continuously in all directions; aligned axes are also permissible. In addition, there is an insensitivity to dust, which is advantageous for the intended use of vibrating plates. 

What is claimed is:
 1. A soil compacting device comprising: an upper mass having a drive; a lower mass connected to the upper mass so as to be movable relative thereto, and having a soil contact plate for soil compaction; an imbalance exciter provided on the lower mass and capable of being driven by the drive; a bearer device situated on one of the upper mass and the lower mass and connected fixedly thereto; the bearer device bearing a transmission device having an input shaft and an output shaft that are coupled together by a torque-transmitting device for transmitting a torque from the input shaft to the output shaft; the bearer device bearing the input shaft and the output shaft so that they are capable of rotation, the drive having a drive shaft that is coupled to the input shaft; the imbalance exciter having an exciter shaft that is coupled to the output shaft; a compensating coupling being provided between the drive shaft of the drive and the input shaft of the transmission device or between the output shaft of the transmission device and the exciter shaft of the imbalance exciter; and the compensating coupling being configured to compensate an axial offset, a radial offset, and an angular offset between one of 1) the drive shaft and the input shaft and 2) between the output shaft and the exciter shaft.
 2. The soil compacting device as recited in claim 1, wherein: the bearer device is fixedly connected to the upper mass; the compensating coupling is provided between the output shaft of the transmission device and the exciter shaft of the imbalance exciter; and the compensating coupling is configured to compensate an axial offset, a radial offset, and an angular offset between the output shaft and the exciter shaft.
 3. The soil compacting device as recited in claim 1, wherein: the bearer device is fixedly connected to the lower mass; the compensating coupling is provided between the drive shaft of the drive and the input shaft of the transmission device; and the compensating coupling is configured to compensate an axial offset, a radial offset, and an angular offset between the drive shaft and the input shaft.
 4. The soil compacting device as recited in claim 3, wherein the bearer device is rigidly connected to at least one of the soil contact plate and an exciter housing appertaining to the imbalance exciter.
 5. The soil compacting device as recited in claim 1, wherein the bearer device and the transmission device are at least partly enclosed by a transmission housing.
 6. The soil compacting device as recited in claim 1, wherein the input shaft is aligned with the drive shaft of the drive in an idle state of the soil compacting device.
 7. The soil compacting device as recited in claim 1, wherein: the transmission device is a belt drive having a first pulley and a second pulley capable of being driven by the first pulley via a belt; the first pulley is borne by the input shaft; the second pulley is borne by the output shaft; and the exciter shaft of the imbalance exciter is coupled to the output shaft and thus to the second pulley in such a way that is capable of being rotationally driven via the second pulley.
 8. The soil compacting device as recited in claim 1, wherein: the compensating coupling is a link coupling that has: a first crank that is coupled to the drive shaft; a second crank that is coupled to the input shaft; and a connecting rod that couples the first crank and the second crank; or the compensating coupling is a link coupling that has: a first crank that is coupled to the output shaft; a second crank that is coupled to the exciter shaft; and a connecting rod that couples the first crank and the second crank.
 9. The soil compacting device as recited in claim 8, wherein the first crank and the second crank are rotated by an angle relative to one another that is bridged by the connecting rod.
 10. The soil compacting device as recited in claim 8, wherein the connecting rod is pivotable relative to at least one of the first crank and the second crank by at least a small angle.
 11. The soil compacting device as recited in claim 8, wherein the connecting rod is coupled to at least one of the first crank and to the second crank via an elastic bearing.
 12. The soil compacting device as recited in claim 11, wherein the elastic bearing is an elastomer spherical bearing.
 13. The soil compacting device as recited in claim 1, wherein at least one of the first crank and the second crank has a compensating mass situated opposite, relative to their axis of rotation, a coupling point at which the connecting rod is coupled.
 14. The soil compacting device as recited in one claim 1, wherein: a centrifugal clutch is provided as part of the drive; and the drive shaft is part of the centrifugal clutch.
 15. A soil compacting device comprising: an upper mass having a drive; a lower mass that is connected to the upper mass so as to be movable relative thereto and that has a soil contact plate for soil compaction; an imbalance exciter that is provided on the lower mass and that is capable of being driven by the drive; a bearer device that is situated on one of the upper mass and the lower mass and that is connected fixedly thereto; wherein the bearer device bears a transmission device having an input shaft and an output shaft that are coupled together by a torque-transmitting device for transmitting a torque from the input shaft to the output shaft; the bearer device bears the input shaft and the output shaft so that they are capable of rotation, the drive has a drive shaft that is coupled to the input shaft; the imbalance exciter has an exciter shaft that is coupled to the output shaft; and further comprising a compensating coupling that is provided between one of 1) the drive shaft of the drive and the input shaft of the transmission device and 2) between the output shaft of the transmission device and the exciter shaft of the imbalance exciter, the compensating coupling being configured to compensate an axial offset, a radial offset, and an angular offset between one of 1) the drive shaft and the input shaft and 2) between the output shaft and the exciter shaft 